Use a direct include of strings headers in chrome_frame/.

chrome_frame/chrome_frame_activex_base.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CHROME_FRAME_CHROME_FRAME_ACTIVEX_BASE_H_
 #define CHROME_FRAME_CHROME_FRAME_ACTIVEX_BASE_H_
 
 #include <atlbase.h>
 #include <atlcom.h>
 #include <atlctl.h>
 #include <exdisp.h>
 #include <wininet.h>
 #include <shdeprecated.h>  // for IBrowserService2
 #include <shlguid.h>
 
 #include <set>
 #include <string>
 #include <vector>
 
 #include "base/metrics/histogram.h"
-#include "base/string_util.h"
-#include "base/stringprintf.h"
+#include "base/strings/string_util.h"
+#include "base/strings/stringprintf.h"
 #include "base/strings/utf_string_conversions.h"
 #include "base/win/scoped_bstr.h"
 #include "base/win/scoped_comptr.h"
 #include "base/win/scoped_variant.h"
 #include "chrome/app/chrome_command_ids.h"
 #include "chrome/common/url_constants.h"
 #include "chrome_frame/chrome_frame_plugin.h"
 #include "chrome_frame/chrome_tab.h"
 #include "chrome_frame/com_message_event.h"
 #include "chrome_frame/com_type_info_holder.h"
@@ skipping 1186 matching lines @@
   EventHandlers onreadystatechanged_;
   EventHandlers onprivatemessage_;
   EventHandlers onextensionready_;
 
   // Handle network requests when host network stack is used. Passed to the
   // automation client on initialization.
   scoped_ptr<UrlmonUrlRequestManager> url_fetcher_;
 };
 
 #endif  // CHROME_FRAME_CHROME_FRAME_ACTIVEX_BASE_H_